Hidden tunnels were found between North Korea and South Korea's borders that will allow thousands of troops to travel in between the DMZ in less than an hour, a discovery which may be frightening for many. A lot of South Koreans are worried there might be more of these tunnels found along the DMZ.

The Korean Demilitarized Zone, or the DMZ, is the borderline between North and South Korea which is fully guarded by military men day and night since their ceasefire in the 1950s. With more than 60 years of so-called peace, would it seem that North Korea still has a hidden agenda? So far, there are a total of four tunnels which have been discovered since the Korean War.

According to a report from Mirror UK, the first one was discovered in the seventies when a defector from North Korea tipped off the military that there are hidden 'invasion' tunnels underneath the DMZ. To the military's surprise they did not find one but four more of these hidden North Korean tunnels.

Although no videos and photos are allowed inside the tunnel, it has been reported that there are sleeping cabins, storage, railway tracks and even electricity in some parts of the tunnel. A report from CNN probes the possibility of North Korea digging a tunnel up to the capital city of Seoul but the Defense Ministry has indicated that it is close to impossible.

The existing tunnels alone have been estimated to be formed for about six years and it would take decades for North Korea to dig a hole through the city, much less go unnoticed for so long. Seeing these as no threat, BBC has reported that some portions of these tunnels have been turned into tourist attractions. However, it still has attracted many tunnel-hunters all over South Korea in the aims of finding more of these 'hidden invasion tunnels'.